This invention relates generally to a method for forming a multi-colored or two-toned decorative outer class A surface or first surface on a skin or panel.
Currently, multicolored or two-tone decorative surfaces are produced on skins or panels by a number of different processes. In general, these processes can be categorized as either coating methods such as painting; or infusion methods such as material pigmenting, i.e., mixing color into plastics materials before the materials are formed into skins or panels.
Processes that employ infusion include slush mold processes where pre-pigmented dry particulate plastic materials are cast against a heated slush mold surface. The cast materials melt on the heated surface to form a shell or skin. Various methods for producing multi-colored or two-tone decorative surfaces includes the use of one or more gaskets in the slush molding process. According to one method, one or more gaskets are used to form a decorative surface on a plastic skin or panel comprising at least two distinct separate areas of plastic material. The gasket is pressed against a heated slush mold surface to separate castings of different-colored charges of dry, particulate plastics material.
Another method for producing multi-colored or two-tone decorative surfaces on skins or panels using pre-pigmented plastic materials includes the masking of certain areas on a heatable slush mold surface. According to this method, a first or xe2x80x9couterxe2x80x9d layer is formed by casting a first plastics material against a portion of the heated mold surface. The masking is then removed and a second or xe2x80x9cinnerxe2x80x9d layer is formed by casting a second plastic material of a different color or shade against the outer layer and also onto the exposed areas of the heated mold surface that had been masked during the first casting step.
Each of the above slush mold methods produces a plastic skin or panel having a composite two-tone outer surface. Because the two plastic materials forming the composite surface are cast against the same heated mold surface they form respective outer surfaces that lie flush in relation to each other. In other words, the composite surface is a single-level, smooth surface.
It is also known, in certain automotive applications, for skins, such as seat upholstery, to include textured surfaces comprising a plurality of small diameter cylindrical depressions or through-holes. The depressions or holes formed in these skins are on the order of one millimeter in diameter and are closely spaced in a regular pattern across an entire outer exposed surfaces of such skins.
What is needed is a quick and accurate method for mass producing skins or panels having multi-colored or two-tone designs on an outer surface of each skin or panel.
According to the invention, a method is provided for forming a design in a panel (12). The method includes providing an outer layer (16), an inner layer (18) and providing the outer layer (16) on the inner layer (18) in a layered disposition. The method further includes providing a design (14) in the panel (12) by forming voids (17) in the outer layer (16) that expose the inner layer (18).
The voids (17) are provided in the outer layer (16) by exposing predetermined regions of the outer layer (16) to a laser beam (32) capable of burning, evaporating or otherwise removing portions of the outer layer (16) in each exposed region. The employment of laser technology allows detailed designs to be created in the outer class A surfaces of large numbers of like panels both quickly and accurately in an assembly line process.